Schedule II-Valuation and Qualifying Accounts (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Allowance for doubtful accounts and returns
Changes in Valuation and Qualifying Accounts
Balance at Beginning of Period		$ 411	$ 1,357	$ 2,390
Charged to Costs and Expenses			(535)	(1,120)
Deductions		(112)	(449)	(17)
Other		6	38	104
Balance at End of Period	305	305	411	1,357
Reserve for excess and obsolete inventory
Changes in Valuation and Qualifying Accounts
Balance at Beginning of Period		22,778	27,517	36,980
Charged to Costs and Expenses	13,400	14,492	1,015	2,015
Deductions		(4,819)	(5,583)	(11,224)
Other		1,150	(171)	(254)
Balance at End of Period	$ 33,601	$ 33,601	$ 22,778	$ 27,517